Sound transmitting device



Filed Oct. 27. 1930 [muerz Patented Sept. 26, 1933 ST TES s mnmsmme Davies II VI IA David FQBurke,Manchester-by-thGSea, Application October 27,1930. seria1No.491,-ss8

f "Fl 17 Claims, (01. 274-37) This invention relates to an improvement in sound transmitting devices and has for its ob- .ject to'provide a device bymeans of which sound vibrations, particularly those from'high-frequency tones, may be transmitted with a minimum amount of, distortion/so that they may-be reproduced without changing their natural quality.

Another object of the invention is to embody in the structure of the device, a means for increasing the intensity of the vibrations without distorting the same. 1

Still another object oil-the invention is to provide a means for dampening; or checking the after vibrations with the result that a more faithful reproduction is obtained, both instrumental music and the human voice being reproduced with equal clarity and without the usual distortion. I I The invention consists ina sound transmitting device as set forth in the following specification and particularly as pointed out in the claims thereofi I Referring to the drawing: I

Fig. 1 represents an enlarged side elevation of a soundtransmitting device embodying'my invention.' I I I I I Fig.2 is an enlarged plan view of the device.

Fig.3 is an enlarged central longitudinal section through the device.

'Like numerals referv to like parts throughout the several views of the drawing. Y

I n the drawing, 5 represents a casing prefer- 'ably constructed of hard vulcanized rubber or other material having similar properties and characteristics. The casing 5* embodies therein a body member 6 and' a closure member 7 which "is separable from the member 6 at 8 in order that access 'may be had to a' chamber 9 which 'is formed withinthe member 6. I I

A sound conducting memberin the form of a needle'or stylus. 10 is located withirran opening 11 providedtherefor in the casing member 6, being rigidly secured therein by means of'a screw 12. The stylus 10 ,is reduced in diameter at 13 and'the "reduced" portion projects a short distance. into the chamber 9.

' Rigidly mounted i n' the casing member '1 is a sound conducting member :14, the upperpor- 'tion f wmchaprmects Predetermmed dlstance rep roduction'o f all the tones transmitted will be obtained. At the same time thevpresence of the small metallic members 18 within the spaceysurabove the pper extremity of the casing member I and terminates ina tapered pointlS. The sound conductingmember 14 is preferably constructed of. the same material as is the'stylus 10 andv is of'the-same diameter as is the main portionof saidstylus, In effect, the sound conducting members 10 and 14 comprise two spacedapart members of a needle or"stylus-,'-the member14being provided for the purpose of receiving and transmitting the sound vibrations and also for securing the device of this invention in wall of said chamber.

a sound reproducing device-in exactly the same i manner as is the ordinary phonograph needle or stylus. T

Located at the bottom of the chamber 9 are a plurality of superposed layers of a thin resilient material, preferably thin rubber discs 16, the lowermost disc of which contacts with the upper extremity-0f the stylus 10. The discs 16 are held seated at the bottom of the chamber 9 by means of a ring 17 which, in turn, is held in position by being cemented to the-wall of the chamber 9. The peripheral portion, furthermore, of the discs 16 may be cemented to the wall of the chamber 9 if it is so desired. Located in the space between the bottom surface of the chamber 9 and the under side of the lower disc 16 are a plurality of metallic members 18 preferably in the form of steel balls, and these members act to stretch the central-portion of the discs 11 upwardly, and portions of certain of said discs contact with the periphery ofthe'reduced portion 13 of the stylus 10. .It is desirable that the metallic members 18 shall be smeared and the spaces therebetween filled with a suitable lubri- 'cantsuch, for example, as Vaseline.

Attached to the lower surface of the casing "member 7, by means of suitable cementgis a ring 19, and cemented'to 'the'under. surface-of the ring 19 is a thin rubber disc 20. Another ring 21 is cemented to theunder surface "of: the disc 20 and'a disc 22 is cemented to the under surface 'of the ring 21. The diameter oftheringslQ and 21' and discs 20 and 2zare-preferably the same as the diameterof the chamber 9, so that when these parts are all assembled, the peripheries of-the rings and discs will contact'with the In transmitting sounds through the device'of this invention the"vibrations in passing from the sound conducting memberlf f through the casing 5' to the-memberf 14, will be'so iniiuencedby the presence of the plurality of rubber discs 16,

the lowermost of which contacts with the'upper extremity of the stylus 10, and by the presence of 'the rings 19 and 21and discs '20 and 22, which are secured to the upper casing member 'lftliat the. .usual after vibrations will be damped 'or checked, with thefresult that a more-faithful roundingv the reduced/portion of the stylus '10 willincrease the intensity of the vibrations for most of the frequencies occurring in speech and "music without causing .them'to bedistorted.- By providing the tapered point upon the upper por- I claim: V

1. A sound transmitting device having, in combination, a casing provided with a chamber therein, a stylus in two parts mounted in said casing, and tympanic membranous members within said chamber and engaging the wal thereof.

2. A sound, transmitting device having, in combination, a casing provided ,witha chamber therein, a stylus in two parts-mounted in said casing, and a plurality of tympanic membranous members spaced apart within said chamber and engaging the wall thereof. 7

3. A sound transmitting device having, in combination, a owing provided with a chamber thereim. astylus in two parts mounted in said casing, and a plurality of tympanic membranous members mounted withinsaid chamber and provided with spaces therebetween. v}

4. 3A soundtransmitting device having, in combination, a casing provided with a chamber therein, a stylus in two parts'mounted in said. casing, and, a tympanic membranous disc within said chamber between the parts of said stylus.

5.. A sound transmitting device having, in combination, a casing, provided with a chamber therein, a stylus in two parts mounted in said casing, and a tympanic membranous disc within said chamber between the parts of said stylus and engaging the wall of said chamber.

6. A sound transmitting device having, in com- .bination,,a casing provided with a chamber therein, a stylus in two parts mounted in said casing,

and a plurality of.-tympanic membranous discs spaced apart within said chamber and engaging the wall thereof. r 1

7. A sound transmitting-device having, in combination, a casing provided with a chamber there in, a stylus in two parts mounted insaid casing, and a tympanic membranous memberwithin said chamber and contacting with the inner extremity of one of the parts of said stylus. i

8. Asound transmitting device having, in combination, a casing provided with a chamber therein, astylus in two parts mounted in said casing,

and a tympanic membranous disc within said chamber contacting ,withthe inner extremityof one of the parts ofsaidstylus and also with the wall of said chamber. 7

9. A sound transmitting device having, in combination, a casing provided with a chamber therein, sound conducting members mounted in said casing, one of said sound conducting members projecting into said chamber, a resilient member within said chamber and contactingwith the inner extremity of said last-mentioned soundconducting member and also with the wall of the chamber, and a mass of small metallic members located within said space surrounding the inner extremity of said last-named sound conducting member.

l 10. A sound transmitting device having/in combination, a casing provided with a chamber therein, a stylus mounted in said casing and comprising .two parts, spaced apart within said chamber, and a tympanic membranous member within said chamber between the extremities of the parts of said stylus and contacting with the wall of the chamber. I

11. A sound transmitting device having, in

.. into the chamber.

prising two parts spaced apart within said chamber, and a plurality of tympanic membranous discs within said chamber between the extremities of the parts of said stylus, one of said discs contacting with the inner extremity of a part 01' the stylus. 12. A- sound transmitting device having, in combination, a casing provided with a chamber "therein, a stylus' mounted in said casing and comprisingtwo parts spaced apart, one of said parts projecting into said chamber, and a plurality of tympanic membranous discs spaced apart within said chamber, one of said discs contacting with the inner extremity of the part of the stylus which projects into the chamber. a

13. A sound transmitting device having, in combination, a casing provided with a chamber therein, a stylus mounted in said casing and comprising two partsspaced apart, one of said -7 parts projecting into said chamber, and atympanic membranous disc within the chamber and loo saidchamber, a, resilient disc within the chamber and engaging thewall thereof, said disc also contacting with the extremity of the stylus, and a mass of small metallic members located within the space surrounding-the reduced portion of the stylus. 1

15. A sound transmitting device having, in combination, a casing provided with a chamber therein, a stylus mounted in said casing and comprising two parts, one of said. parts projecting into said chamber "and the other of said parts terminating at its outer extremity in a point and being adapted to be attached to a sound reproducing device, and a tympanic membranous disc within said chamber contacting with the extremity of said stylus that projects into said chamber and also with the wall of the chamber.

16. A sound transmitting device having, in combination, a casing provided with a chamber .therein, a stylus imounted in said casing and comprising two parts, one of said parts projectinto the chamber and also with the wall of the chamber, and a mass of spherical metallic members located beneath said last-named disc and surrounding the portion of the stylus which contacts with said disc. e

1'7. A sound transmitting device having, in combination, a casing provided with a chamber therein, a stylus mounted in said casing and comprisingtwo parts, one of said parts .projecting into said chamber and both of the .parts projecting outwardly from opposite sides of the casing, and a plurality of tympanic membranous wall thereof, one of thediscs also contacting with the inner extremity ofsaid'stylus that projects oavm F. BURKE.

discs within said chamber contacting with the 

